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91.
92.
Dong-Li Zhang Chao-Qun Li Wei-Kang Li Jian-Xi Li 《Fullerenes, Nanotubes and Carbon Nanostructures》2017,25(4):250-255
A facile strategy for the preparation of water-soluble multi-walled carbon nanotubes (MWCNTs) in aqueous solution is proposed, where MWCNTs were treated by the concentrated mix acid and then functionalized by simultaneous radiation-induced graft polymerization of acrylic acid under the γ-ray. The structure of the grafted MWCNTs (denoted as MWCNT-g-PAAc) is characterized by means of FT-IR, lH NMR, Raman spectroscopies, TGA analysis, and TEM imaging. The degree of grafting was dependent on the reaction conditions such as the monomer concentration and the inhibitor concentration. The stability of the aqueous solution of MWCNT-g-PAAc is highly improved, where the solution is stable for more than 30 days at the concentration 1.5 g/L. 相似文献
93.
Flexible Nonvolatile Transistor Memory with Solution‐Processed Transition Metal Dichalcogenides 下载免费PDF全文
Richard Hahnkee Kim Jinseong Lee Kang Lib Kim Suk Man Cho Dong Ha Kim Cheolmin Park 《Small (Weinheim an der Bergstrasse, Germany)》2017,13(20)
Nonvolatile field‐effect transistor (FET) memories containing transition metal dichalcogenide (TMD) nanosheets have been recently developed with great interest by utilizing some of the intriguing photoelectronic properties of TMDs. The TMD nanosheets are, however, employed as semiconducting channels in most of the memories, and only a few works address their function as floating gates. Here, a floating‐gate organic‐FET memory with an all‐in‐one floating‐gate/tunneling layer of the solution‐processed TMD nanosheets is demonstrated. Molybdenum disulfide (MoS2) is efficiently liquid‐exfoliated by amine‐terminated polystyrene with a controlled amount of MoS2 nanosheets in an all‐in‐one floating‐gate/tunneling layer, allowing for systematic investigation of concentration‐dependent charge‐trapping and detrapping properties of MoS2 nanosheets. At an optimized condition, the nonvolatile memory exhibits memory performances with an ON/OFF ratio greater than 104, a program/erase endurance cycle over 400 times, and data retention longer than 7 × 103 s. All‐in‐one floating‐gate/tunneling layers containing molybdenum diselenide and tungsten disulfide are also developed. Furthermore, a mechanically‐flexible TMD memory on a plastic substrate shows a performance comparable with that on a hard substrate, and the memory properties are rarely altered after outer‐bending events over 500 times at the bending radius of 4.0 mm. 相似文献
94.
Multicolor Photo‐Crosslinkable AIEgens toward Compact Nanodots for Subcellular Imaging and STED Nanoscopy 下载免费PDF全文
Xiaofeng Fang Xuanze Chen Rongqin Li Zhihe Liu Haobin Chen Zezhou Sun Bo Ju Yifei Liu Sean Xiao‐An Zhang Dan Ding Yujie Sun Changfeng Wu 《Small (Weinheim an der Bergstrasse, Germany)》2017,13(41)
Aggregation induced emission (AIE) has attracted considerable interest for the development of fluorescence probes. However, controlling the bioconjugation and cellular labeling of AIE dots is a challenging problem. Here, this study reports a general approach for preparing small and bioconjugated AIE dots for specific labeling of cellular targets. The strategy is based on the synthesis of oxetane‐substituted AIEgens to generate compact and ultrastable AIE dots via photo‐crosslinking. A small amount of polymer enriched with oxetane groups is cocondensed with most of the AIEgens to functionalize the nanodot surface for subsequent streptavidin bioconjugation. Due to their small sizes, good stability, and surface functionalization, the cell‐surface markers and subcellular structures are specifically labeled by the AIE dot bioconjugates. Remarkably, stimulated emission depletion imaging with AIE dots is achieved for the first time, and the spatial resolution is significantly enhanced to ≈95 nm. This study provides a general approach for small functional molecules for preparing small sized and ultrastable nanodots. 相似文献
95.
The issues of hydrogen generation and storage have hindered the widespread use and commercialization of hydrogen fuel cell vehicles.It is thus highly attractive,but the design and development of highly active non-noble-metal catalysts for on-demand hydrogen release from alkaline NaBH4 solution under mild conditions remains a key challenge.Herein,we describe the use of CoP nanowire array integrated on a Ti mesh (CoP NA/Ti) as a three-dimensional (3D) monolithic catalyst for efficient hydrolytic dehydrogenation of NaBH4 in basic solutions.The CoP NA/Ti works as an on/off switch for on-demand hydrogen generation at a rate of 6,500 mL/(min.g) and a low activation energy of 41 kJ/mol.It is highly robust for repeated usage after recycling,without sacrificing catalytic performance.Remarkably,this catalyst also performs efficiently for the hydrolysis of NH3BH3. 相似文献
96.
97.
《工程(英文)》2017,3(5):731-737
Due to increasing safety concerns regarding human consumption of fish products, an increasing number of medicinal chemicals are prohibited from use in aquaculture. As a result, Chinese herbal medicines are being increasingly used, coining the use of the term “green medicine.” Research shows that Chinese herbal medicines have many beneficial effects on fish, including growth promotion, enhancement of disease resistance, and improvement in meat quality. Many effective ingredients have been discovered in Chinese herbal medicines, which function to promote feed intake, improve meat flavor, and increase digestive enzyme activity. They also regulate and participate in processes that improve the specific and non-specific immunity of fish; however, the composition of Chinese herbal medicines is very complex and it is often difficult to identify the effective ingredients. This article reviews the latest research and application progress in Chinese herbal medicines regarding growth and feed utilization, immunity and disease resistance, and the meat quality of cultured fish. It also discusses research on the chemical constituents of classical Chinese medicinal herbs and problems with the application of Chinese herbal medicines in fish culture. This article concludes by proposing that future studies on Chinese herbal medicines should focus on how to cheaply refine and extract the effective ingredients in classical Chinese medicinal herbs, as well as how to use them efficiently in aquaculture. 相似文献
98.
Experimental and modeling progress and results aiming to increase the color uniformity of hemisphere-type pcW-LEDs are proposed. By adding micrometric zirconia particles, the light scattering is enhanced, that induces a decrease of phosphor necessary to obtain a specific CCT. The optical model is able to determine the optical properties (CCT, angular CCT distribution, chromaticity and packaging efficiency) in a hemisphere LED for various amount of YAG-phosphor and ZrO2-zirconia particles. Based on previous process, the work is in the first step to fit the effective radius and refractive index that will be implemented in the optical model. In the second step, the optical model is compared with the experimental measurement to determine the absorption coefficient and conversion efficiency of a package of silicone resin containing phosphor and zirconia. Finally, the model, confirmed by selected experimental results, allows determining the optical properties of any king of package that lead to a CCT emission ranging from 4500 K to 6500 K. The analysis of these data is interpreted by comparing, for a specific CCT, the phosphor loss, the packaging efficiency and the angular distribution of CCT. The results show that if the effort is targeted on one of the previous parameters, there is always a counterpart on the other ones. Increasing the color uniformity will induce to decrease the packaging efficiency. 相似文献
99.
100.
Monitoring the Dynamic Process of Formation of Plasmonic Molecular Junctions during Single Nanoparticle Collisions 下载免费PDF全文
Jing Guo Jie Pan Shuai Chang Xuewen Wang Na Kong Wenrong Yang Jin He 《Small (Weinheim an der Bergstrasse, Germany)》2018,14(15)
The capability to study the dynamic formation of plasmonic molecular junction is of fundamental importance, and it will provide new insights into molecular electronics/plasmonics, single‐entity electrochemistry, and nanooptoelectronics. Here, a facile method to form plasmonic molecular junctions is reported by utilizing single gold nanoparticle (NP) collision events at a highly curved gold nanoelectrode modified with a self‐assembled monolayer. By using time‐resolved electrochemical current measurement and surface‐enhanced Raman scattering spectroscopy, the current changes and the evolution of interfacial chemical bonding are successfully observed in the newly formed molecular tunnel junctions during and after the gold NP “hit‐n‐stay” and “hit‐n‐run” collision events. The results lead to an in‐depth understanding of the single NP motion and the associated molecular level changes during the formation of the plasmonic molecular junctions in a single NP collision event. This method also provides a new platform to study molecular changes at the single molecule level during electron transport in a dynamic molecular tunnel junction. 相似文献